* [PATCH] Fix up Yr constraint
@ 2016-05-24 18:40 Jakub Jelinek
2016-05-24 20:47 ` Uros Bizjak
0 siblings, 1 reply; 4+ messages in thread
From: Jakub Jelinek @ 2016-05-24 18:40 UTC (permalink / raw)
To: Uros Bizjak, Kirill Yukhin, Ilya Enkovich; +Cc: gcc-patches
Hi!
The Yr constraint contrary to what has been said when it has been submitted
actually is always NO_REX_SSE_REGS or NO_REGS, never ALL_SSE_REGS, so
the RA restriction to only the first 8 regs is done no matter what we tune
for.
This is because we test X86_TUNE_AVOID_4BYTE_PREFIXES, which is an enum
value (59), rather than actually checking if the tune flag.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2016-05-24 Jakub Jelinek <jakub@redhat.com>
* config/i386/i386.h (TARGET_AVOID_4BYTE_PREFIXES): Define.
* config/i386/constraints.md (Yr): Test TARGET_AVOID_4BYTE_PREFIXES
rather than X86_TUNE_AVOID_4BYTE_PREFIXES.
--- gcc/config/i386/i386.h.jj 2016-05-24 10:56:02.000000000 +0200
+++ gcc/config/i386/i386.h 2016-05-24 15:13:05.715906018 +0200
@@ -465,6 +465,8 @@ extern unsigned char ix86_tune_features[
ix86_tune_features[X86_TUNE_SLOW_PSHUFB]
#define TARGET_VECTOR_PARALLEL_EXECUTION \
ix86_tune_features[X86_TUNE_VECTOR_PARALLEL_EXECUTION]
+#define TARGET_AVOID_4BYTE_PREFIXES \
+ ix86_tune_features[X86_TUNE_AVOID_4BYTE_PREFIXES]
#define TARGET_FUSE_CMP_AND_BRANCH_32 \
ix86_tune_features[X86_TUNE_FUSE_CMP_AND_BRANCH_32]
#define TARGET_FUSE_CMP_AND_BRANCH_64 \
--- gcc/config/i386/constraints.md.jj 2016-05-12 10:29:41.000000000 +0200
+++ gcc/config/i386/constraints.md 2016-05-24 15:14:21.647914550 +0200
@@ -142,7 +142,7 @@ (define_register_constraint "Yf"
"@internal Any x87 register when 80387 FP arithmetic is enabled.")
(define_register_constraint "Yr"
- "TARGET_SSE ? (X86_TUNE_AVOID_4BYTE_PREFIXES ? NO_REX_SSE_REGS : ALL_SSE_REGS) : NO_REGS"
+ "TARGET_SSE ? (TARGET_AVOID_4BYTE_PREFIXES ? NO_REX_SSE_REGS : ALL_SSE_REGS) : NO_REGS"
"@internal Lower SSE register when avoiding REX prefix and all SSE registers otherwise.")
(define_register_constraint "Yv"
Jakub
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] Fix up Yr constraint
2016-05-24 18:40 [PATCH] Fix up Yr constraint Jakub Jelinek
@ 2016-05-24 20:47 ` Uros Bizjak
2016-05-24 21:36 ` Jakub Jelinek
0 siblings, 1 reply; 4+ messages in thread
From: Uros Bizjak @ 2016-05-24 20:47 UTC (permalink / raw)
To: Jakub Jelinek; +Cc: Kirill Yukhin, Ilya Enkovich, gcc-patches
On Tue, May 24, 2016 at 6:55 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> Hi!
>
> The Yr constraint contrary to what has been said when it has been submitted
> actually is always NO_REX_SSE_REGS or NO_REGS, never ALL_SSE_REGS, so
> the RA restriction to only the first 8 regs is done no matter what we tune
> for.
>
> This is because we test X86_TUNE_AVOID_4BYTE_PREFIXES, which is an enum
> value (59), rather than actually checking if the tune flag.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
>
> 2016-05-24 Jakub Jelinek <jakub@redhat.com>
>
> * config/i386/i386.h (TARGET_AVOID_4BYTE_PREFIXES): Define.
> * config/i386/constraints.md (Yr): Test TARGET_AVOID_4BYTE_PREFIXES
> rather than X86_TUNE_AVOID_4BYTE_PREFIXES.
Uh, another brown-paper bag bug...
OK everywhere.
Thanks,
Uros.
> --- gcc/config/i386/i386.h.jj 2016-05-24 10:56:02.000000000 +0200
> +++ gcc/config/i386/i386.h 2016-05-24 15:13:05.715906018 +0200
> @@ -465,6 +465,8 @@ extern unsigned char ix86_tune_features[
> ix86_tune_features[X86_TUNE_SLOW_PSHUFB]
> #define TARGET_VECTOR_PARALLEL_EXECUTION \
> ix86_tune_features[X86_TUNE_VECTOR_PARALLEL_EXECUTION]
> +#define TARGET_AVOID_4BYTE_PREFIXES \
> + ix86_tune_features[X86_TUNE_AVOID_4BYTE_PREFIXES]
> #define TARGET_FUSE_CMP_AND_BRANCH_32 \
> ix86_tune_features[X86_TUNE_FUSE_CMP_AND_BRANCH_32]
> #define TARGET_FUSE_CMP_AND_BRANCH_64 \
> --- gcc/config/i386/constraints.md.jj 2016-05-12 10:29:41.000000000 +0200
> +++ gcc/config/i386/constraints.md 2016-05-24 15:14:21.647914550 +0200
> @@ -142,7 +142,7 @@ (define_register_constraint "Yf"
> "@internal Any x87 register when 80387 FP arithmetic is enabled.")
>
> (define_register_constraint "Yr"
> - "TARGET_SSE ? (X86_TUNE_AVOID_4BYTE_PREFIXES ? NO_REX_SSE_REGS : ALL_SSE_REGS) : NO_REGS"
> + "TARGET_SSE ? (TARGET_AVOID_4BYTE_PREFIXES ? NO_REX_SSE_REGS : ALL_SSE_REGS) : NO_REGS"
> "@internal Lower SSE register when avoiding REX prefix and all SSE registers otherwise.")
>
> (define_register_constraint "Yv"
>
> Jakub
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] Fix up Yr constraint
2016-05-24 20:47 ` Uros Bizjak
@ 2016-05-24 21:36 ` Jakub Jelinek
2016-05-25 9:00 ` Uros Bizjak
0 siblings, 1 reply; 4+ messages in thread
From: Jakub Jelinek @ 2016-05-24 21:36 UTC (permalink / raw)
To: Uros Bizjak; +Cc: Kirill Yukhin, Ilya Enkovich, gcc-patches
On Tue, May 24, 2016 at 08:35:12PM +0200, Uros Bizjak wrote:
> On Tue, May 24, 2016 at 6:55 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> > Hi!
> >
> > The Yr constraint contrary to what has been said when it has been submitted
> > actually is always NO_REX_SSE_REGS or NO_REGS, never ALL_SSE_REGS, so
> > the RA restriction to only the first 8 regs is done no matter what we tune
> > for.
> >
> > This is because we test X86_TUNE_AVOID_4BYTE_PREFIXES, which is an enum
> > value (59), rather than actually checking if the tune flag.
> >
> > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
> >
> > 2016-05-24 Jakub Jelinek <jakub@redhat.com>
> >
> > * config/i386/i386.h (TARGET_AVOID_4BYTE_PREFIXES): Define.
> > * config/i386/constraints.md (Yr): Test TARGET_AVOID_4BYTE_PREFIXES
> > rather than X86_TUNE_AVOID_4BYTE_PREFIXES.
>
> Uh, another brown-paper bag bug...
>
> OK everywhere.
I fear it might be too dangerous for -mavx512* for the branches; I went
through all the Yr uses on the trunk, but not on the branches.
Would you be ok with using
"TARGET_SSE ? (TARGET_AVOID_4BYTE_PREFIXES ? NO_REX_SSE_REGS : SSE_REGS) : NO_REGS"
on the branches instead?
Or I guess we could use it on the trunk too, it should make no difference there
(because on the trunk it is only used when !TARGET_AVX).
Or maybe even
"TARGET_SSE ? ((TARGET_AVOID_4BYTE_PREFIXES && !TARGET_AVX) ? NO_REX_SSE_REGS : SSE_REGS) : NO_REGS"
(again, should make zero difference on the trunk, but might be better for
the branches).
> > --- gcc/config/i386/i386.h.jj 2016-05-24 10:56:02.000000000 +0200
> > +++ gcc/config/i386/i386.h 2016-05-24 15:13:05.715906018 +0200
> > @@ -465,6 +465,8 @@ extern unsigned char ix86_tune_features[
> > ix86_tune_features[X86_TUNE_SLOW_PSHUFB]
> > #define TARGET_VECTOR_PARALLEL_EXECUTION \
> > ix86_tune_features[X86_TUNE_VECTOR_PARALLEL_EXECUTION]
> > +#define TARGET_AVOID_4BYTE_PREFIXES \
> > + ix86_tune_features[X86_TUNE_AVOID_4BYTE_PREFIXES]
> > #define TARGET_FUSE_CMP_AND_BRANCH_32 \
> > ix86_tune_features[X86_TUNE_FUSE_CMP_AND_BRANCH_32]
> > #define TARGET_FUSE_CMP_AND_BRANCH_64 \
> > --- gcc/config/i386/constraints.md.jj 2016-05-12 10:29:41.000000000 +0200
> > +++ gcc/config/i386/constraints.md 2016-05-24 15:14:21.647914550 +0200
> > @@ -142,7 +142,7 @@ (define_register_constraint "Yf"
> > "@internal Any x87 register when 80387 FP arithmetic is enabled.")
> >
> > (define_register_constraint "Yr"
> > - "TARGET_SSE ? (X86_TUNE_AVOID_4BYTE_PREFIXES ? NO_REX_SSE_REGS : ALL_SSE_REGS) : NO_REGS"
> > + "TARGET_SSE ? (TARGET_AVOID_4BYTE_PREFIXES ? NO_REX_SSE_REGS : ALL_SSE_REGS) : NO_REGS"
> > "@internal Lower SSE register when avoiding REX prefix and all SSE registers otherwise.")
> >
> > (define_register_constraint "Yv"
Jakub
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] Fix up Yr constraint
2016-05-24 21:36 ` Jakub Jelinek
@ 2016-05-25 9:00 ` Uros Bizjak
0 siblings, 0 replies; 4+ messages in thread
From: Uros Bizjak @ 2016-05-25 9:00 UTC (permalink / raw)
To: Jakub Jelinek; +Cc: Kirill Yukhin, Ilya Enkovich, gcc-patches
On Tue, May 24, 2016 at 9:02 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Tue, May 24, 2016 at 08:35:12PM +0200, Uros Bizjak wrote:
>> On Tue, May 24, 2016 at 6:55 PM, Jakub Jelinek <jakub@redhat.com> wrote:
>> > Hi!
>> >
>> > The Yr constraint contrary to what has been said when it has been submitted
>> > actually is always NO_REX_SSE_REGS or NO_REGS, never ALL_SSE_REGS, so
>> > the RA restriction to only the first 8 regs is done no matter what we tune
>> > for.
>> >
>> > This is because we test X86_TUNE_AVOID_4BYTE_PREFIXES, which is an enum
>> > value (59), rather than actually checking if the tune flag.
>> >
>> > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
>> >
>> > 2016-05-24 Jakub Jelinek <jakub@redhat.com>
>> >
>> > * config/i386/i386.h (TARGET_AVOID_4BYTE_PREFIXES): Define.
>> > * config/i386/constraints.md (Yr): Test TARGET_AVOID_4BYTE_PREFIXES
>> > rather than X86_TUNE_AVOID_4BYTE_PREFIXES.
>>
>> Uh, another brown-paper bag bug...
>>
>> OK everywhere.
>
> I fear it might be too dangerous for -mavx512* for the branches; I went
> through all the Yr uses on the trunk, but not on the branches.
> Would you be ok with using
> "TARGET_SSE ? (TARGET_AVOID_4BYTE_PREFIXES ? NO_REX_SSE_REGS : SSE_REGS) : NO_REGS"
> on the branches instead?
> Or I guess we could use it on the trunk too, it should make no difference there
> (because on the trunk it is only used when !TARGET_AVX).
> Or maybe even
> "TARGET_SSE ? ((TARGET_AVOID_4BYTE_PREFIXES && !TARGET_AVX) ? NO_REX_SSE_REGS : SSE_REGS) : NO_REGS"
> (again, should make zero difference on the trunk, but might be better for
> the branches).
Indeed, let's play safe and go with the later version on branches.
Please also add a small comment, to avoid head-scratching in the
future.
Uros.
^ permalink raw reply [flat|nested] 4+ messages in thread
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2016-05-24 18:40 [PATCH] Fix up Yr constraint Jakub Jelinek
2016-05-24 20:47 ` Uros Bizjak
2016-05-24 21:36 ` Jakub Jelinek
2016-05-25 9:00 ` Uros Bizjak
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